Packing for piston rods and the like



Aug. 24 ,1926. G. 'H. ROBINSON PACKING FOR-PISTON ROD$ AND THEILIKE Filed March 11, 1926 77 m w m 6. w 6 0 DM 06 C .L M 1 do d d 0 F q q M 1 f\ I d Patented Aug. 24, 1 2

UNITED STATES 1,597,290 PATENT. OFFICE.

GEORGE HUNTER ROBINSON, OF LONDON, ENGLAND, ASSIGNOR TO THE BELDAM PACK- ING AND RUBBER COMPANY, LIMITED, OF LONDON, ENGLAND.

PACKING FOR PISTON RODS AND THE LIKE.

Application filed March 11,1926, Serial No. 94,012, and in Great Britain November 18, 1924.

This invention relates to flexible metallic or semi-metallic packing for piston rods and the like of the kind comprisinga bar of double wedge shape in section adapted 5 to be folded together to form a V in order to complete its formation as a packing. Under modern conditions of increasing high temperatures and pressures the working face of the packing must be as hardas possible in order to resist both wear and fusion but with the methods hitherto adopted in connection with packing of the kindto which the invention relates it isimpossible to se cure the required degree of hardness con- 1 sistent with flexibility necessary to enable the packing to be bent. V i

The object of the present invention is to overcome the above difficulty and the invention consists in metallioor semi-metallic packing comprising a bar of double wedge shape in section adaptedto be foldedtogether to form a V, the double wedge parts being of suitable metal to form the working face while the junction between such parts is formed of a suitable ductile metal embodied in the bar and enabling the parts of the bar to be bent and folded together.

The invention also consists in other details and arrangements hereinafter described or indicated.

The accompanying drawings illustrate two modes of carrying out the invention.

Figure 1 is a sectional elevation of a mould with a ductile metal strip therein.

Figure 2 is a section of the composite metallic packing formed by the apparatus of Figure 1.

Figure 3 is a plan of the packing with an asbestos or like backing secured thereto.

Figure 4 is a plan showing a part of the metallic packing bent round to engage a piston or other rod.

Figure 5 is a view of the packing shown in Figure 2 bent into a V shape.

Figure 6 is a view of a modified form of packing, and y t Figure 7 shows the asbestos or like backing.

In carrying my invention into effect in one convenient manner, as, for example, in its application to a metallic packing of the kind comprising a bar of white metal or other anti-friction or hearing metal of approximately double wedge-shaped section provided upon each side with saw-cuts or gaps placed in staggered relation to one another and such that the bar may be subseguently bent up from the sides to form an approximate V shape, I employ a mould or die comprising two parts, a, b, (Figure 1) one of which, a, is shaped to give the double wedge-shaped section, and within the mould or die I place a strip 0 of soft ductile metal of the. required length and size, the strip extending, for the full length of the die or mould which corresponds to the length of the bar to be formed. The central part of the strip is gripped tightly between the two mould parts at the centre and the strip projects or extends for a predetermined distance into each side of the mould, the eX- tending or projecting part beingserrated or having a cleaned and roughened surface or being otherwise formed or treated to secure the necessary adhesion between such strip and the hard anti-friction metal which is subsequently run into the mould to form the double wedge parts (Z which subsequently form the wearing face of the packing.

The anti-friction metal may be run into the mould at a temperature which is somewhat higher than the melting point of the flexible or ductile strip so that when the two metals come into contact there will be a slight surface flow of the ductile metal allowing the two to amalgamate at their surfaces.

Alternatively, the strip may be tinned to secure proper adhesion, or it may be formed with holes therein so that the anti-friction metal will key itself to' the strip by lodgment within said holes, or in general any suitable method may be adopted to secure the intimate contact and proper adhesion between the two metals.

In this way I am enabled to produce a bar, the wearing face of which may be of any desired hardness while the median portion of thebar will be of sufficient flexibility to enable the bar to be bent up from the sides to an approximate V formation.

In an alternative arrangement shown in Figure 6, I may provide a plurality of thin strips 6 superposed upon one another so that their central portions are tightly gripped between the mould parts while the portions projecting into the hollow mould may be separated from one another or spread substantially fan-wise so that when the antifriction metal is run into the mould it will flow freely between the separated parts of the sheets and thus make for itself a secure anchorage, but will not flow between the st'a p 'ered relation toone another in known at: manner and after having been bent to required d ameter, the ring may be passed round'aifotatlng abrasion 'niandril of a de Vterniined tlialneter sothat the wearing faces otthebar may be ground to'the truecircle required, it 'beingevident that the greater 5 the 'nuniberoii' slots and separate wearing face'sin a bar of given length the less will be the grinding necessary 'to arrive at a l true circle.

When "a 'bar accordance with the invention 15 to be used in coniblnatlon with asbestos or otherllke non rnetalhc material (Figure?) the b'ar niaybefirmly and securely attached toa piece. of asbestos cloth or'canvas'or oth'ersuitablematerial h (Figure 3,) "by wire staples ior otherwise after which it is bent into its V form and is then inserted into the asbestos or other noninet allicin'aterial andrubber, the cloth that is attached to the bar being passed round the outside of the asbestos or like channel. and the whole being. then finally vulcanized in a suitable mould under pressure.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is: v

l. Metallicor'semi-inetallic packing comprising a bar of double wedge shap e'in section adapted' to 'be folded togetlmr-to form a V, the double wedge parts being of suitable metal to form the working face while the junction between-such parts "is formed of a suitable ductile metal embodied in the bar and en'ablihg'the parts oithebarto be bent "and folded together.-

2(Me'tallic or semi-metallic packing according to claim 1 in which fadhesion or amalgamation "of the two diii'erent metals composing the baris'proinoted by treatment the ductile metal portion; 7

3. manic or semi-metallic packing according'to claim 1 in which the ductile portion consists of a plurality of thin sheets superposed one iipon another. '7 a j 4. Metallic or'senii-nietallic packing according to claim 1 and having transverse slots staggered in relation to one another said slots being" cut right through the hard part ofthe bar and extending-a short distance into the soft flexible back portion.

Intestim'ony whereof I have signed my name to this specification.

GEORGE HUNT-ER ROBINSON. s 

